No abstract

No abstract

Publication costs assisted by the University of CaliforniaSpecific rate constants for the unimolecular decomposition of cyclobutanone (CB), 3-oxetanone (OXTN), and perfluorocyclobutanone (PFCB) have been calculated by the general RRKM computer program of Hase and Bunker. PFCB is calculated to react slower and OXTN faster than CB for a given photoactivation energy, The calculation supports the internal conversion mechanism in the photolysis of PFCB, and it predicts that the observable pressure quenching of the internally converted intermediate in the photolysis of OXTN would occur above 1 atm. For CB and PFCB, the experimental values can be fitted to the calculated values using a stepladder deactivation model for 3,-6 kcal/mol lost per collision for the CB (Sot)-propylene pair. Conversion of photoactivation energy to product translation is discussed. IntroductionThe RRKM (Rice-Ramsperger-Kassel-Marcus) theory

The feasibility of measuring the H-atom quantum yield ( ) in the photolysis of H2CO by the + cis-2-butene and + 1-butene addition reactions below 1 Torr has been studied. This chemical trapping method provides fairly reliable results below ~300 nm. The single vibronic level values of extrapolated to zero-pressure are 0.68 ± 0.10 at 275.4 nm, ~0.6 at 288.2 nm, and 0.68 ± 0.05 at 303.5 nm. These values are in good agreement with the very recent values of Horowitz and Calvert.

A sensitive and quantitative spectroscopic method of detecting the hydrogen atoms formed in photolysis has been developed. The near infrared emmision from HNO (Ã A′′→Ã 1A′) produced by recombination of H and NO is monitored.